基于可持续发展的IS—LM—SD模型

可持续发展是经济、社会和环境三者和谐发展的统一,不仅与一个国家的自然资源禀赋有关,而且与国家的财政、货币政策等制度安排有着内在的联系,表现为产品市场、货币市场和与社会、环境相关的特殊服务市场的均衡,因此,国家可以通过财政政策、货币政策的合理应用,实现社会、经济、生态环境的协调发展。通过把社会可持续发展曲线和环境可持续发展SE曲线合并成可持续发展SD曲线,纳入到IS—LM模型中去,得出了国家可以通过财政、货币政策调整SH影响经济发展,影响产品市场、货币市场和特殊服务品市场的均衡,实现经济、社会、生态环境的可持续发展的结论。     

考虑入流角的水平井筒混合损失模型

对水平井的孔眼入流处的微元段进行了流动分析,根据气、液两相的连续性方程、动量方程和能量方程,在相间不存在传质和等温稳态流动等条件下,得到了气、液两相的混合损失计算模型。根据得到的模型,计算了不同入流角条件下水平井筒混合损失的值,结果表明:入流角对混合损失的影响较大,在不影响产量等条件下,应尽量采用小于90°的入流角,有利于减小井筒的压降。本模型对改变传统的射孔方式、鱼刺型分支井和压裂水平井的研究具有一定的指导意义。     

知识经济环境下加强无形资产财务管理的思考

为了满足知识经济环境下对财务管理的要求,针对目前无形资产在财务管理中弱化的表现,提出了相应对策,以完善财务管理的内容。     

5-(l-氧基)-2(5H)-呋喃酮的不对称1,3-偶极环加成反应

5- (l-氧基 )- 2 (5H)- 呋喃酮在温和的实验条件下 ,能够同环状硝酮发生立体选择性的环加成反应 ,得到立体专一性产物 ,化学产率 54%～ 81% .     

Parasite fauna of the grey mullet Mugil cephalus L. 1758, and its relationship with some ecological factors in Lower Kızılırmak Delta located by the Black Sea,Turkey

Parasites of the grey mullet <i>Mugil cephalus</i> collected from Lower K?z?l?rmak Delta in Turkey were investigated. <i>Trichodina puytoraci</i>, <i>Trichodina lepsii</i>, <i>Ligophorus mediterraneus</i>, <i>Ligophorus cephali</i>, <i>Gyrodactylus</i> sp., <i>Microcotyle mugilis</i>, <i>Ascocotyle (Phagicola) longa</i>, <i>Haplosplanchnus pachysomus</i>, <i>Diplostomum spathaceum</i>, <i>Tylodelphys clavata</i>, <i>Posthodiplostomum</i> sp., <i>Neoechinorhyncus agilis</i> and <i>Ergasilus lizae</i> were identified. Overall infection prevalence (%), mean intensity and mean abundance values were 99.61%, 458.10 ± 75.72 and 456.30 ± 75.44, respectively. Infection indices of parasite species in relation to season, lakes/lagoons and some physicochemical parameters of water such as temperature, salinity, dissolved oxygen and nitrate are determined and discussed. <i>Posthodiplostomum</i> sp. is a new parasite record for mugilids and <i>Diplostomum spathaceum</i> is the first record in <i>M. cephalus</i>, in the present study. Moreover, <i>Ligophorus mediterraneus</i>, <i>Ligophorus cephali</i> and <i>Ergasilus lizae</i> are new records for Turkish parasite fauna of fish and <i>Mugil cephalus</i> is a new host record for <i>Neoechinorhyncus agilis</i> in Turkey.     

基于零空间l1范数最小化的ISAR成像方法

在目标场景散射率分布满足稀疏性假设下,压缩感知(compressive sensing, CS)成像与传统距离-多普勒成像方法相比,可以使用很少的数据获得良好的图像,图像对比度高,没有旁瓣干扰。本文提出了一种基于零空间l₁范数最小化的逆合成孔径雷达(inverse synthetic aperture radar, ISAR) CS成像方法。从解欠定方程组的角度,将待重建目标图像分解为初猜值与残余值两部分。首先使用加权最小二乘(weighted lease square, WLS)法估计初猜值,作为目标初像；然后将待重建目标场景散射率的l₁范数作为额外的一个非线性测量值引入到图像重建中,在卡尔曼滤波框架下,利用非线性“伪测量”值,最小化待重建目标场景的l₁范数来估计零空间中残余值的解。实测ISAR数据处理验证了所提算法的有效性。与正交匹配追踪算法(matching pursuit algorithm, OMP)和primal-dual l₁范数最小化方法相比,所提方法获得的成像效果更好,成像时间比primal-dual l₁范数最小化方法更短。     

Approximation methods of mixed l_1/H_2 optimization problems for MIMO discrete-time systems

The mixed l1/H2 optimization problem for MIMO (multiple input-multiple output) discrete-time systems is considered. This problem is formulated as minimizing the l1-norm of a closed-loop transfer matrix while maintaining the H2-norm of another closed-loop transfer matrix at prescribed level. The continuity property of the optimal value in respect to changes in the H2-norm constraint is studied. The existence of the optimal solutions of mixed l1/H2 problem is proved. Because the solution of the mixed l1/H2 problem is based on the scaled-Q method, it avoids the zero interpolation difficulties. The convergent upper and lower bounds can be obtained by solving a sequence of finite dimensional nonlinear programming for which many efficient numerical optimization algorithms exist.     

Control of the cardiovascular system ofAplysia by identified neurons

The neural network that controls the cardiovascular system of<i>Aplysia</i> adapts cardiovascular function to a variety of different physiological and behavioral situations. It (1) coordinates the cardiovascular system with the renal and respiratory systems; (2) modifies both systemic and regional blood flow during food-elicited arousal and feeding; and (3) changes the tension of longitudinal vascular muscle to adapt the arterial tree to changes in body shape. Indirect evidence suggests that the cardiovascular control circuit may also play a role in maintaining homeostasis during egg laying. Several putative neurotransmitters, including acetylcholine, serotonin, R15<img src="/content/n688g2qr6422185l/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">1 and R15<img src="/content/n688g2qr6422185l/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">2 peptides, have been localized to identified neurons in this circuit.     

Evidence for the extranuclear localization of thymosins in thymus

A new radioimmunoassay has been developed for thymosin <img src="/content/u060l2vp75368616/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"><sub>4</sub> by generating rabbit polyclonal antibodies against the synthetic N-terminal peptide fragment 1–15 coupled to KLH. The synthetic analogue [Tyr<sup>12</sup>]-thymosin <img src="/content/u060l2vp75368616/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"><sub>4</sub> (1–15) was used as tracer. This radioimmunoassay, with a useful range of 10–1000 pmoles, showed cross-reactivity with the second homologous <img src="/content/u060l2vp75368616/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-thymosin of man and rat (thymosin <img src="/content/u060l2vp75368616/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"><sub>10</sub>) but not of calf (thymosin <img src="/content/u060l2vp75368616/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"><sub>9</sub>). This radioimmunoassay, together with an improved radioimmunoassay for the N-terminus of parathymosin <img src="/content/u060l2vp75368616/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">, was employed for the measurement of the levels of thymosin <img src="/content/u060l2vp75368616/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"><sub>4</sub> and parathymosin <img src="/content/u060l2vp75368616/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> in nuclear and extranuclear extracts of calf thymus. The bulk of these polypeptides was found in the extranuclear material whereas only traces were observed in the nuclear environment, which indicates the extranuclear localisation of <img src="/content/u060l2vp75368616/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">- and <img src="/content/u060l2vp75368616/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-thymosins.     

基于稀疏重构的跳频信号检测方法

针对复杂电磁环境下跳频信号的检测问题,提出了一种基于稀疏重构的跳频信号检测方法,首先采用近似l0范数算法对含有干扰的跳频信号进行稀疏重构,采用拟牛顿法求解无约束多维最优化问题,然后对得到的时频图的频率分量进行二值形态学滤波以去除干扰和噪声,最后通过统计匹配信号的个数完成信号的检测。同时为提高算法的自适应能力,在选取二值化阈值时采用最大类间方差法。理论分析和仿真实验表明该算法在较低信噪比下仍能克服干扰和噪声并较好地保存各跳,实现对跳频信号的检测。